The present invention relates to a plasma display panel (PDP) and its manufacturing method, and specifically to a plasma display panel with driving circuits one-sidedly and its manufacturing method.
Cathode ray tubes (CRTs) have been widely used as TV displays and excel in resolution and picture quality. However, the depth and weight of CRTs sharp increase as the screen size increases. Therefore, in order to obtain a planar, full-colored, high-resolution TV with a large screen size (particularly exceeding 40 inches), the plasma display panel (PDPs) having a large screen size and a short depth is getting more and more attention. The PDP is lightened by plasma discharges and has millions of pixels. In detail, each pixel is formed as a discharge cell filled with inert gases. The inner wall of the cell is coated by a fluorescent material consisting of red (R), green (G), or blue (B) ultraviolet excited material. When a high voltage is exerted on the discharge cell, a plasma of the inert gases is introduced and an ultraviolet light is produced by the plasma in order to excite the fluorescent material to radiate red, green, or blue light.
FIG. 1 is a perspective view of a conventional PDP, and FIG. 2 is a sectional view of the conventional PDP shown in FIG. 1 along A-Axe2x80x2 line. The PDP is mainly composed of a front substrate 12 and a rear substrate 11. The front substrate 12 includes a pair of scanning electrodes 13, a dielectric layer 14, and a protecting layer 16. The dielectric layer 14 is covered on the scanning electrode 13, and the protecting layer 16, preferably a MgO layer, is used for protecting the scanning electrode 13 and maintaining surface charges on the scanning electrode 13. The rear substrate 11 includes an addressing electrode 17 and a dielectric layer 18 for covering and protecting the addressing electrode 17. The directions of the scanning electrode 13 and that of the addressing electrode 17 are about perpendicular to each other. In addition, the PDP further includes a barrier rib 19 between the front 12 and rear substrates 11 for defining a plurality of the discharge cells 1. Each cell has a fluorescent material 10 coated on the inner wall and a mixed gas of xenon (Xe) and neon (Ne) sealed therein. When a high voltage is exerted at the electrodes 13 and 17, plasma discharges are activated in the discharge cells to excite the fluorescent material 10 to radiate visible lights. Further, the PDP further includes a sealing frit 15 between the front 12 and rear 11 substrates for sealing the two substrates.
The directions of the scanning electrode 13 and the addressing electrode 17 are about perpendicular to each other and the lengths of the two substrates are different from each other, so the edges of the two substrates are exposed after the two substrates 11xe2x80xa212 are sealed. Therefore, some parts of the bonding electrodes 131xe2x80xa2171 on both substrates 11xe2x80xa212 are exposed as shown in FIG. 3. The exposed portions of the bonding electrodes 131xe2x80xa2171 will be linked to two outer driving circuits (not shown) and driven by these driving circuits respectively. Since the sealing frit 15 does not have enough strength before glazing, the substrates must be compressed to seal until the sealing frit is completely glazed so as to prevent the position of the substrates from shifting and to maintain the distance between substrates. Therefore, the whole sealing process of the conventional PDP is very complicated, including two coating and glazing steps to maintain that the related position of the substrates. After the sealing process, two driving circuits for driving PDP are bonded on the substrates in direction A and direction B respectively, as shown in FIG. 3. Because the direction A is opposite to the direction B, it needs at lease two mounting steps to bond these driving circuits. This is very time-consuming and inconvenient.
It is therefore attempted by the applicant to deal with the above situation encountered with the prior art.
An object of the present invention is to provide a plasma display panel (PDP) and its manufacturing method. The PDP includes two glass substrates having electrodes thereon respectively, and the length of one substrate is longer than the other. The PDP further includes a bonding electrode and a conductive device for changing the power-supplying route of the electrode on the small substrate.
Another object of the present invention is to provide a PDP with driving circuits one-sidedly and its manufacturing method.
A further object of the present invention is to provide a PDP manufacturing method that is easy to sealing and positioning the two glass substrates.
The PDP of the present invention includes a first substrate having a first edge, a second substrate spaced apart from the first substrate, a first electrode positioned on the first substrate along a first direction, a second electrode positioned on the second substrate along a second direction, a bonding electrode, and a conductive device. The second direction of the second electrode is substantially perpendicular to the first direction of the first electrode. The first substrate has a first length and the second substrate has a second length shorter than the first length. The bonding electrode is disposed on the first edge of the first substrate uncovered by the second substrate. The conductive device has a first and a second conductive pads, the first conductive pad is protruded from the bonding electrode, and the second conductive pad is protruded from the second electrode and contacting with the first conductive pad. The bonding electrode on the first substrate is electrically connected with an outer circuit such that the second electrode of the second substrate is electrically connected with the outer circuit through the conductive device and the bonding electrode.
According to the present invention, the PDP further includes a sealing frit disposed between the first and the second substrates for sealing the two substrates. Besides, the PDP includes a barrier rib disposed between the first and the second substrates for defining a discharge cell or a plurality of discharge cells. The sealing frit can be positioned between the conductive device and the first edge of the first substrate or between the conductive device and the barrier rib.
A method for manufacturing the PDP described as above includes the steps of: (a) forming a first electrode on the first substrate along a first direction; (b) forming a bonding electrode on a first edge of the first substrate uncovered by the second substrate, and forming a first conductive pad on the bonding electrode; (c) forming a second electrode on the second substrate along a second direction, and forming a second conductive pad on a first end of the second electrode, the second direction being substantially perpendicular to the first direction; (d) connecting the first conductive pad with the second conductive pad, and bonding the first and the second substrates so that the second electrode of the second substrate is electrically connected to the bonding electrode of the first substrate; and (e) forming a sealing frit around the first substrate for sealing the first substrate and the second substrate. Alternatively, another method for manufacturing the PDP described as above includes the steps of: (a) forming a first electrode on the first substrate along a first direction; (b) forming a bonding electrode on a first edge of the first substrate uncovered by the second substrate, and forming a first conductive pad on the bonding electrode; (c) forming a second electrode on the second substrate along a second direction, and forming a second conductive pad on a first end of the second electrode, the second direction being substantially perpendicular to the first direction; (d) forming a sealing frit between the first electrode and the bonding electrode for sealing the first substrate and the second substrate; and (e) connecting the first conductive pad with the second conductive pad, and bonding the first substrate and the second substrate so that the second electrode of the second substrate is electrically connected to the bonding electrode of the first substrate.
According to another aspect of the present invention, the plasma display panel (PDP) connected with an outer circuit includes a first substrate having a tipper surface and a second substrate having a lower surface. The upper surface includes a covered region and an exposed region, the exposed region has a first edge, and the second substrate has a second edge. The second substrate is positioned above the covered region of the first substrate, the lower surface of the second substrate faces the upper surface of the first substrate, and the exposed region of the first substrate being protruded from the second edge of the second substrate. The PDP further includes a signal electrode, a bonding electrode, a first conductive pad, and a second conductive pad. The signal electrode is disposed on the lower surface of the second substrate and extended to the second edge of the second substrate. The bonding electrode is disposed on the upper surface of the first substrate and extending from the covered region to the exposed region. Besides, the bonding electrode above the exposed region of the first substrate is connected to the outer circuit. The first conductive pad is protruded from the upper surface of the first substrate and electrically connected with the bonding electrode, and the second conductive pad is protruded from the lower surface of the second substrate to contact with the first conductive pad and electrically connected with the signal electrode. The bonding electrode is electrically connected with the outer circuit and the signal electrode is electrically connected with the bonding electrode through the first and the second conductive pads so that the signal electrode is electrically connected to the outer circuit.
The present invention may best be understood through the following description with reference to the accompanying drawings, in which: